Vacuum cleaner with controllable brush

ABSTRACT

A vacuum cleaner comprises a vacuum cleaner main body having a vacuum resource and a dust-collecting receptacle for the drawn dust; a suction part main body connected with the vacuum cleaner main body in fluid-communication; a rotating brush mounted to the suction part main body; a driving pulley mounted to the rotating brush; an idle pulley disposed adjacent to the driving pulley; a belt located on one of the driving pulley or the idle pulley, and on an axis of the vacuum resource; a belt guide unit having a belt guide member moved between the first position connecting the belt with the driving pulley and the second position connecting the belt with the idle pulley; and a belt guide member controller for moving the belt guide member to one of the first position and the second position.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of Korean Patent Application No. 2004-023101 filed on Apr. 2, 2004, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates to a vacuum cleaner. More particularly, the present invention relates to a vacuum cleaner having a controllable rotating cleaning brush.

BACKGROUND OF THE INVENTION

Generally, a vacuum cleaner has a vacuum resource, and draws in dust particles, dirt and other contaminants by a suction force generated by a motor-drive vacuum resource. By drawing in contaminants, the suction force is used to clean a surface.

As is well known, however, certain surfaces and places are difficult to clean by only a vacuum. Depending on the type of surface and the kind of dirt, dust and contaminant to be cleaned, some surfaces and some kinds of contaminants can be more effectively picked up by a vacuum cleaner by the use of a rotating brush in combination with a suction force. As is also known, however, use of a rotating brush is not always necessary. For example, when the vacuum cleaner user does not want the noise that is generated by friction between the rotating brush and the cleaning surface, or when cleaning a surface or an object that can be damaged by the rotating brush, it is necessary to stop the rotating brush. In vacuum cleaners equipped with a rotating brush, cleaning work can be performed without a rotating brush can be performed using various cleaning accessory tools attached to the vacuum source by a hose. If a rotating brush is not needed for cleaning, the ability to stop the rotating brush would, among other things, enable a vacuum cleaner motor to direct all of its available power to the vacuum fan or other vacuum source, reduce wear on the rotating brush when its not needed and reduce noise caused by the brush's rotation. Accordingly, a need exists for a vacuum cleaner which can selectively control a rotating cleaning brush according to required cleaning circumstances or desired operation.

U.S. Pat. No. 6,044,520 discloses a vacuum cleaner controlling the driving of rotating brush. However, the vacuum cleaner disclosed in this patent has a very complicated structure such that the size of the main body gets bigger, and accordingly, the manufacturing cost increases.

SUMMARY OF THE INVENTION

There is provided a vacuum cleaner having a controllable rotating brush.

The vacuum cleaner comprises a vacuum cleaner main body having a vacuum resource, prior art embodiments of which are well-known to those of ordinary skill in the art. The vacuum also includes a dust-collecting receptacle for the drawn-in dust, dirt and other contaminants. A suction part main body that runs over a surface to be cleaned, is connected with the vacuum cleaner main body and in fluid-communication with the main body by a vacuum passage way.

The suction part main body includes a belt-driven rotating brush. The rotating brush includes a drive pulley over which a belt runs but which also runs over a drive motor output shaft. Rotation of the drive pulley by the belt causes the rotating brush to rotate. The rotating brush includes a free-wheeling idler pulley that is disposed adjacent to and co-axial with the driving pulley.

A belt is directed to ride on either the driving pulley or the free-wheeling idler pulley by way of a belt guide unit having a belt guide member that is moved between a first position that directs the belt onto the driving pulley and a second position that directs the drive connecting the belt onto the idler pulley. A belt guide member controller moves the belt guide member to either one of the first position and the second position. The belt guide unit further comprises a spring for biasing the belt guide member toward the first position.

In a preferred embodiment, the belt guide member controller is a belt control knob belt control knob rotatably mounted to the suction part main body by which the belt guide member is moved between the first position and the second position by the contact with the belt guide member. In the preferred embodiment, the belt control knob comprises a knob rotatably mounted in the suction part main body, and a cam member configured as a half cylinder. The cam member contacts the belt guide member when the knob part is located in a certain position, and for moving the belt guide member to the second position.

The belt guide member controller is mounted to the suction part main body, and is a button unit for moving the belt guide member to one of the first position and the second position by a button operation.

The button unit comprises a button exposed to the suction part main body; a press member contacted with a lower portion of the button, and moved to the press direction of the button according to the movement of the press operation of the button; a return spring contacted with a lower portion of the press member; and a lever of which one end is located on a lower portion of the press member, and the other end is attached to the belt guide member. The lever is moved according to the movement of the lower portion of the press member to move the belt guide member to the first position and the second position.

The cleaner main body is inclinably mounted to the suction part main body, and has a cam member at the lower portion. When the cleaner main body is substantially upright, the cleaner main body is contacts the belt guide member in such a way to prevent the belt guide member from moving to the first position.

The belt guide member comprises a first member of which one end restricts and moves the belt to one of the first position and the second position, and the other end is attached to the suction part main body by screws; a second member connected with the first member and extended to the cleaner main body by a certain length, and when the cleaner main body is substantially upright, the second member is contacted with cam member of a lower portion of the cleaner main body to prevent the first member from moving to the first position.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features and advantages of the present invention will be more apparent from the following detailed description taken with reference to the accompanying drawings, in which:

FIG. 1 is a perspective view of a vacuum cleaner according to an embodiment of the present invention;

FIG. 2 is a bottom view of FIG. 1 with a belt missing;

FIG. 3 is a perspective view from another angle, of portion D of FIG. 2 including a belt;

FIG. 4 is a detailed view of a belt guide unit of FIG. 3;

FIG. 5 is a bottom view of FIG. 1 when a selection knob of a belt guide member controller is located on a driving position;

FIG. 6 is a bottom view of FIG. 1 when the selection knob of the belt guide member controller is located on non-driving position;

FIG. 7 shows a cleaner body and the belt guide member in operation;

FIG. 8 shows the cleaner main body and the belt guide member in operation, when the cleaner body is locked to the suction body;

FIG. 9 is a bottom view of FIG. 8, when the selection knob is located on the driving position;

FIG. 10 is a view of the belt guide member controller according to another embodiment of the present invention; and

FIG. 11 and FIG. 12 are detailed views of a button unit of FIG. 10.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the following description, drawing reference numerals are used for the same elements in different drawings. The embodiments described herein are only examples and not intended to be limiting. Rather, the invention disclosed herein is set forth in the appurtenant claims. Also, well-known functions and structures are not described in detail since they would tend to obscure the invention in unnecessary detail.

FIG. 1 is a perspective view of an upright type vacuum cleaner 100. FIG. 2 is a bottom view of the suction part 10 shown in FIG. 1 but without a belt so as to better show detail. FIG. 3 is a perspective view of the bottom of the suction part 10 viewed from another angle and including a belt. FIG. 4 is a detail view of a belt guide unit in the suction unit 10.

As shown in the drawings, the vacuum cleaner 100 comprises a suction part 10 that runs over a floor, carpet or other cleaning surface (not shown) to be cleaned by vacuuming. A cleaner body 20 is mounted to the suction part 10 so that it can be rotated about an axis 29 and inclined with respect to the cleaning surface over which the suction part 10 is operated. Two or more wheels 26 are provided in a rear side of the suction part 10 to allow the vacuum cleaner 100 to be moved about on a cleaning surface. A main body locking/release lever 30 is located at the rear and lower end of the main body 20. The vacuum can be operated using the handle 24 that is connected with and forms a portion of the main body 20.

The cleaner main body 20 has therein a motor-driven vacuum resource (not shown), and a dust-collecting receptacle (not shown). The cleaner main body 20 is rotatably attached to the suction part 10 such that it can incline upwardly and downwardly about an axis 29, with respect to a cleaning surface over which the vacuum cleaner 100 is to be used.

The motor driven vacuum source within the cleaner main body 20 is in fluid-communication with the suction part 10, which is the part of the vacuum cleaner 100 through which contaminants are taken up from a cleaning surface. The fluid communication between the motor driven vacuum source and the suction part allows the vacuum provided by the vacuum source to be extended into the suction part 10. Accordingly, contaminants in air from a cleaning surface enter the vacuum cleaner 100 via the suction part 10 and are carried into a dust-collecting receptacle (not shown) of the cleaner main body 20.

The locking/release lever 30 is provided at a lower portion of the cleaner main body 20 for locking the cleaner main body 20 at a substantially upright position with respect to the suction part 10. The locking/release lever 30 also serves to release the cleaner main body 20 from the substantially upright position to allow the cleaner main body 20 to be upwardly and downwardly inclined with respect to the suction part 10 and the cleaning surface over which the suction part 10 is operated. As such, a user pushes the locking/release lever 30 of the cleaner main body 20 by use of a hand or foot to release the cleaner main body 20. The user can thereafter operate the cleaner main body 20 to clean a cleaning surface. When cleaning is finished, or when an extension hose or the other accessories need to be attached to the vacuum cleaner 100, the vacuum cleaner body 20 is adjusted to the substantially upright position as shown in FIG. 1. Cam members 22 (refer to FIG. 7) are provided at a lower portion of the cleaner main body 20. This will be explained below in greater detail.

Referring to FIGS. 1 and 2, the suction part 10 of the vacuum 100 comprises a suction part main body 14, a rotating brush 12, a height adjustment knob 27 for adjusting the height of the suction part 10, a driving pulley 42, an idle pulley 44, a belt guide unit 50 and a belt guide member controller.

The rotating brush 12 is shaped like a right circular cylinder. It is rotatably mounted in the suction part body 14 on bearings (not shown) that are preferably located at each end of the rotating brush 12 such that the rotating brush 12 can easily spin on its axis of rotation (not shown). The rotation brush 12 includes a plurality of bristle members (not shown), which are planted or inserted along the outer circumference surface of the rotating brush 12. The bristles extend away from the outer circumference surface of the rotation brush 12 and act to dislodge dirt from a surface contacted by the rotating brush bristles.

In a preferred embodiment, the rotating brush 12 is belt driven to rotate about its axis and receives driving force from a motor (not shown) in the cleaner main body 20.

The driving pulley 42 is fixedly attached to the rotating brush 12 such that rotation of the driving pulley 42 causes the rotating brush 12 to rotate when a belt 46 is on the driving pulley 42 and moving. The idler pulley 44, which is located adjacent to the driving pulley 42, is free-wheeling on bearings or a bearing surface such idler pulley 44 rotation does not impart rotation to the rotating brush 12.

Referring to FIG. 3, the rotating brush belt 46 is selectively directed to ride over one of the driving pulley 42 or the idle pulley 44 and is driven by a rotating axis 28 of a motor, preferably embodied as the motor for the vacuum resource (not shown). When the belt 46 is directed to ride over the driving pulley 42, the rotating brush 12 is rotated by force transmitted to the driving pulley 42 through the belt 46 from from the vacuum resource axis 28.

Referring to FIG. 2 through FIG. 4, the belt guide unit 50 comprises a belt guide member 52 and a spring 56. The belt guide member 52 restricts the belt 46 to move between the first position A (FIG. 2) wherein the belt 46 runs over the aforementioned driving pulley 42, and the second position B (FIG. 2) wherein the belt 46 runs over the free-wheeling idler pulley 44, in which case, the rotating brush 12 is not driven.

As shown in FIG. 3 and FIG. 4, the belt guide member 52 comprises a first member 53 and a second member 54. The first member 53 is sized structured and arranged to engage the belt 46, with one end of the first member 53 directing the belt by restricting the belt 46 to either the first position “A” or the second position “B.” The other end of the belt guide member 52 is rotatably attached to the suction part 10 main body 14 by screw or other post 55 about which the belt guide member 42 can rotate or pivot. The second member 54 of the belt guide member 52 is connected with the first member 53 and extends inwardly, i.e., towards center of the suction part 10 as shown.

A spring 56 for the belt guide member 52 is mounted to the suction part main body 14 around the aforementioned screw or post 55, prior to when the belt guide member 52 is fixedly attached to the suction part main body 14, such that the belt guide member 52 is biased by the spring 56 toward the first position “A” for the belt 46 such that the belt 46 rides over the driving pulley 42.

A belt guide member controller embodied in part as a belt control knob, controls the movement of the belt guide member 52 to be in either the first position “A” or the second position “B.” The belt control knob has a knob part 63 that extends through the top of the suction part 10 and can be seen in FIG. 1. The knob part 63 of the belt control knob extends to a cam member 64 as seen in FIGS. 2, 3, 5 and 6, is used to direct belt guide member 52 from the top of the suction part 10 whereby a user of the vacuum cleaner 100 can control the operation of the rotating brush 12. As shown in FIG. 1, the knob part 63 is exposed to the suction part main body 14, and is rotatably mounted to have a driving or non-driving position in which the rotating brush 12 is either driven or not driven. As shown in the figures, the cam member 64 is formed in the shape of as a half cylinder.

In one embodiment, when the knob part 63 is rotated to drive the rotation brush 12, the cam member 64 does not contact the belt guide member 52. Rather, the belt guide member 52 is urged to locate the belt 46 by the return spring 56 to the first position “A” indicated as a dotted line in FIG. 2. As a result, belt 46 is restricted by the first member 53 of the belt guide member 52 to wind around or ride over the driving pulley 42 such that the rotating brush 12 is driven to rotate. If the knob part 63 is selected to a non-driving position, the cam member 64 is rotated with the knob part 63 to urge the first member 53 of the belt guide member 52 to move the belt guide member 52 to the second position “B” indicated as a solid line in FIG. 2. As such, the belt 46 is then restricted by the first member 53 of the belt guide member 52 to wind over or ride over the free wheeling idler pulley 44 such that the rotating brush 12 does not receive power through the belt 46. It is important to note that frictional losses between the free-wheeling idler pulley 44 and its bearing between it and the rotating brush 12 may continue to impart a small amount of torque to the rotating brush 12, however, power required to rotate the brush 12 is not provided to the rotating brush 12 through the free-wheeling pulley 44 and the rotating brush 12 is considered to be un-powered or stopped.

The operation of the vacuum cleaner 100 having the above structure according to the foregoing is hereafter described in detail with reference to the accompanying drawings.

FIGS. 5 through 7 show the locking of the vacuum cleaner main body 20 released from the suction part 10, that is, when the vacuum cleaner main body 20 is not substantially upright to the suction part 10.

Referring to FIG. 5, if the knob part 63 is selected to the driving position, the belt guide member 52 is not contacted with the cam member 64, and is moved to the first position “A” (refer to FIG. 2) by the return spring 56. As such, the belt 46 winds over the driven pulley 42 and is driven by the vacuum resource axis 28 and restricted by the first member 53 of the belt guide member 52.

Referring to FIG. 6, when the knob part 63 is selected to a non-driving position, the first member 53 of the belt guide member 52 controls the cam member 64, which in turn directs the belt guide member 52 to forcibly move to the belt 46 to the second position “B” (referring to FIG. 2). As such, when the belt 46 winds over the free-wheeling idler pulley 44, no driving torque is provided to the rotating brush 12.

FIG. 7 shows the operating relationship of the vacuum cleaner main body 20 and the belt guide member 52. The vacuum cleaner main body cam member 22 is mounted to a lower portion of the main body 20 and is rotated in relation to movement of the vacuum cleaner 20. The groove 22 a has a certain width C. As shown in FIG. 7, if the vacuum cleaner main body 20 is released from being locked to the suction part 10, the vacuum cleaner main body 20 can be adjusted to a position other than the upright position with respect to the suction part 10. The second member 54 of the belt guide member 52 contacts the groove 22 a of the vacuum cleaner main body cam member 22. As mentioned above, when the belt guide member 52 is moved to the first position “A” (refer to FIG. 2) by the spring 56, and the second member 54 of the belt guide member 52 is moved within the certain width C of the groove 22 a so, the belt guide member 52 does not interfere with the vacuum cleaner main body cam member 22. The belt guide member 52 is then moved to the first position “A” and the second position “B” in accordance with the driving or non-driving position of the knob part 63 as shown in FIG. 5 and FIG. 6. Therefore, the belt 46 is restricted by the belt guide member 52 to be wound over the driving pulley 42 or the idle pulley 44 in accordance with the driving or non-driving position of the knob part 63, and the rotating brush 12 is driven or not driven.

When a vacuum cleaner is used with the vacuum cleaner body 20 released from the upright position to clean the floor, the rotating brush 12 is automatically driven or not driven according to the selection position of driving or non-driving of the knob part 63.

FIGS. 8 and 9 are partial views showing when the vacuum cleaner main body 20 is locked to the suction part 10 in a substantially upright position. Referring to FIG. 8, the belt guide member 52 is restricted to move to the first position “A” by the interference with the vacuum cleaner main body cam member 22. In particular, the vacuum cleaner cam member 22 is rotated counter clock-wise according to the movement of the vacuum cleaner main body 20, and therefore, the second member 54 of the belt guide member 52 is contacted with the partition 22 b of the vacuum cleaner main body cam member 22. As such, the second member 54 of the belt guide member 52 is contacted with the partition 22 a of the vacuum cleaner main body cam member 22, and therefore, the belt guide member 52 can not be moved to the first position A and is located in the second position B (refer to FIG. 2). Finally, the belt 46 restricted by the belt guide member 52 is wound the idle pulley 44, and the rotating brush 12 is not driven.

As shown in FIG. 9, even though the knob part 63 is selected to a driving position, the belt guide member 52 is located in the second position B owning to the interference with the partition 22 b of the vacuum cleaner main body cam member 22 and the second member 54. Finally, the belt 46 restricted by the first member 53 of the belt guide member 52 is wound on the idle pulley 44, and the rotating brush 12 is not driven. If the knob part 63 is selected to a non-driving position, the belt guide member 52 is positioned in the second position “B” as shown in FIG. 9, because of the interference of the cam member 64 with the belt control knob and the first member 53 of the belt guide member 52, and the interference of the partition 22 b of the vacuum cleaner main body cam member 22 and the second member 54 of the belt guide member 52. The belt restricted by the first member 53 of the belt guide member 52 is wound on the idle pulley 44, and the rotating brush 12 is not driven.

When a vacuum cleaner is stowed after cleaning, or when operates with use of an extension hose and various accessories, the vacuum cleaner main body 20 is locked to the suction part 10 in a substantially upright position, and therefore, the rotating brush 12 is not driven, irrespective of the selection position of driving or non-driving of the knob part 63. Even though a user inadvertently turns on the power of the vacuum resource, the rotating brush is not driven with the cleaner main body 20 in a substantially upright position, and therefore, damage to the surface being cleaned due to abrupt rotation of the rotating brush, is prevented.

FIGS. 10 through 12 are views of a second embodiment.

Similar to the embodiment set forth above, when the vacuum cleaner main body 20 is in its substantially upright position, the belt guide member 52 is located in the second position “B” (FIG. 2) by the belt guide member 52. As such, the belt 46 restricted by the belt guide member 52 to wound over the free wheeling idler pulley 44. The rotating brush 12 is therefore not driven. In the first embodiment, when the vacuum cleaner main body 20 is not in a substantially upright position, but down in an operating other position, the position of the belt guide member 52 is adjusted in accordance with the driving or non-driving selection position of the knob part 63 of the belt control knob, and the belt 46 restricted by the belt guide member 52 to be wound over the driving pulley 42 or the idle pulley 44. In the second embodiment, the position of the belt guide member 52 is adjusted by the button unit 70.

As shown in FIGS. 10 through 12, the button unit 70 comprises a button 72 cap exposed on and accessible from the exterior of the suction part main body 14. When depressed, the button 72 actuates a press member 73 that contacts the lower portion of the button 72 and moves downwardly in response to actuation of the button 72. A coil return spring 74 is seated against the bottom of the press member 73 and acts to keep the button 72 biased upwardly. A press member stop spring 75 is mounted against the bottom of the the return spring 74 to bias the press member 73 from moving further when the press member 73 is located in a certain position. One end of the lever 76 is coupled to the lower portion of the press member 73. The other end of the lever 76 moves against the belt guide member 52 of the belt guide unit 50 in the direction of the free wheeling idler pulley 44 when the lever 76 rotates around the pivot 78. The housing 77 provides an enclosure and mounting for the button 72, the press member 73, the return spring 74, the stop spring 75 and the lever 76 and pivot 78.

When the vacuum cleaner main body 20 is not in a substantially upright position, but in other positions, the belt guide member 52 is located on the first position “A” (refer to FIG. 2) by the spring 56 and the belt 46 is restricted by the first member 53 of the belt guide member 52 to wind over the driving pulley 42. Therefore, the rotating brush 12 is driven. If the button 72 is pressed for a non-driven mode of operation, the press member 73 coupled with the button 72 is moved in the direction of the lower portion of the button 72. The lever 76 rotates on about the axis 78 so that one end 76 a of the lever 76 is moved in the direction of the lower portion of the press member 73 by the movement of the press member 73. The other end 76 b of the lever 76 engaged with the belt guide member 52 moves the belt guide member 52 to the second position B (refer to FIG. 2) indicated as a solid line in FIG. 10. The belt 46 restricted by the first member 53 of the belt guide member 52 is wound on the idle pulley 44 according to the movement of the belt guide member 52, and the rotating brush 12 is not driven.

If the button 72 is pressed again, the press member 73 is returned to its starting position by the return spring 56, and the lever 76 is returned to its starting position by the return of the press member 73. The belt guide member 52 connected with the other end 76 b of the lever 76 is located to the first position “A” (refer to FIG. 2) indicated as a dot line of FIG. 10, and the belt 46 winds over the driving pulley 42. Therefore, the rotating brush 12 is driven to operate.

If the button unit 70 is depressed, when the locking of the vacuum cleaner main body 20 is released, and when the vacuum cleaner main body 20 is not in a substantially upright position, but in other positions, the rotating brush 12 is driven/not driven according to a simple button operation. As such, a user can easily operate the vacuum cleaner.

With a vacuum cleaner according to the present invention as described above, the operation of the rotating brush is easily controlled by a simple belt guide member controller. As such, the operation of the rotation brush 12 can be conveniently controlled as needed to reduce noise, wear on the brush, wear on a surface and reduce energy use by disengaging the rotating brush from its driving motor.

The foregoing embodiment and advantages are merely exemplary and are not to be construed as limiting the present invention. The description of the embodiments of the present invention is intended to be illustrative, and not to limit the scope of the claims, and many alternatives, modifications, and variations will be apparent to those skilled in the art. 

1. A vacuum cleaner comprising: a vacuum cleaner main body having a vacuum resource and a dust-collecting receptacle for the drawn dust; a suction part main body connected with the vacuum cleaner main body in fluid-communication therewith; a rotating brush mounted to the suction part main body; a driving pulley mounted to the rotating brush; an idler pulley disposed adjacent to the driving pulley; a belt located on one of the driving pulley or the idler pulley, and on an axis of the vacuum resource; a belt guide unit having a belt guide member moved between the first position connecting the belt with the driving pulley and the second position connecting the belt with the idler pulley; and a belt guide member controller for moving the belt guide member to one of the first position and the second position.
 2. The vacuum cleaner according to claim 1, wherein the belt guide unit further comprises: a spring for biasing the belt guide member toward the first position.
 3. The vacuum cleaner according to claim 2, wherein the belt guide member controller is a belt control knob rotatably mounted to the suction part main body and for moving the belt guide member to one of a first position or a second position by the contact with the belt guide member when the belt control knob is rotated.
 4. The vacuum cleaner according to claim 3, wherein the belt control knob comprises: a knob part exposed to the suction part main body and rotatably mounted to the main body, and a cam member configured as a half cylinder, wherein the cam member is contacted with the belt guide member when the knob part is located on a certain position, and for moving the belt guide member to the second position.
 5. The vacuum cleaner according to claim 1, further comprising: a cam member contacted with the belt guide member to prevent the belt guide member from moving to the first position when the cleaner main body is substantially upright, wherein the cleaner main body is inclinably mounted to the suction part main body.
 6. The vacuum cleaner according to claim 5, wherein the belt guide member comprises: a first member of which one end restricts and moves the belt to one of the first position or the second position, and the other end is attached to the suction part main body; a second member connected with the first member and extended to the cleaner main body by a certain length, and when the cleaner main body is substantially upright, the second member is contacted with the cam member of the cleaner main body to prevent the first member from moving to the first position.
 7. The vacuum cleaner according to claim 2, wherein the belt guide member controller is: a button unit mounted to the suction part main body and for moving the belt guide member to one of the first position or the second position by a button operation.
 8. The vacuum cleaner according to claim 7, wherein the button unit comprises: a button exposed to the suction part main body; a press member contacted with a lower portion of the button, and moved to the press direction of the button according to the movement of the press operation of the button; a return spring contacted with a lower portion of the press member; and a lever of which one end is located on a lower portion of the press member, and the other end is attached to the belt guide member, wherein the lever is moved according to the movement of the lower portion of the press member to move the belt guide member to the first position or the second position.
 9. The vacuum cleaner according to claim 8, wherein the button unit further comprises: a stop spring located on the return spring, and for preventing the press member from further moving to the press direction when the press member is located on a certain position; and a housing for at least the return spring and the stop spring. 